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View Full Version here: : New camera, back to the beginning with 47 Tuc


The_bluester
04-01-2019, 12:29 PM
So, I rapidly got the irrits with the old Canon I was using and lashed out on a ZWO ASI294 MC Pro OSC camera. After two nights of false starts for clouds, mount and software issues I got a bit of data last night on 47 Tuc


Target: 47 Tuc (Obviously)
Cam: ASI294MC Pro
Scope: Celestron C925 with a 0.63 reducer.
Subs from 5 to 60 seconds (Cant recall total integration time)
Stacked in Deep Sky Stacker and (Rough, the only kind I am capable of) processed in GIMP.


Loads of issues to work through yet, some saturated stars, stars not really round and tight (Combination most likely of guiding, mount issues, focus, collimation etc) and the processing is a bit rugged.



All the same, a promising start for the new cam. Now I need to disassemble my mount and work out why the RA axis is not behaving, it has a clutch issue where the clutch appears to be locked up, you cant readily move the RA axis by hand, the motor is running and the worm turning, but the axis is not moving. Some tolerance jiggling to be done I think, obviously something is fouling and locking the axis up but the clutch is not driving it.

The_bluester
04-01-2019, 03:57 PM
So, I spent the afternoon with the mount in bits. The AZEQ6/Atlas Pro are not a robust design in one way at least, mine has not done a whole lot of work but the design of the clutch levers encourages you to do them up fairly tight, that compresses the felt clutch discs and they are effectively a spacer in the mount. When they compress, the action of doing up the clutch pulls the moving part of the axis (So the puck on the Dec and the main mount head in RA) downward toward the fixed part, in my case the discs had compressed far enough that the setting circles were binding on the moving parts of the mount, and the clutch itself will not engage properly so I was having odd guiding results and occasionally with the RA worm still turning the mount would actually just stop moving. I can't recall the clutch mechanism in detail when I helped Andy01 with an EQ6 needing repair, but the bearing setup is totally different, the bearings in those are tapered rollers in tension like a traditional car front hub and the clutch works differently. On the AZEQ design the nuts that people will see as equivalent to the tension nuts on an EQ6 are really only there to stop it falling apart when you release the clutches. The end float in an EQ6 stays the same clutch released or engaged, but the AZEQ has no end float with the clutch engaged and maybe a millimeter of it when it it not.


I have made some 280gsm card shims and suddenly I can feel the RA and Dec backlash, which I realise I could not before. Now to track down some new clutch felt discs, the heavy paper card ones will be OK to test for now and make sure it is going to do the job but in winter they will attract moisture and turn in to mush.

xelasnave
04-01-2019, 05:28 PM
Looks good so far.
Actually really good for first run.
You seem to have a great attitude so things can inly improve...keep them coming.
Alex

The_bluester
04-01-2019, 06:53 PM
The problem is I am sure I will outrun the C925 as a photography tool in fairly short order, time will tell. I know the collimation was not quite on the money either, but with the hassles I was having with the mount I did not spend much time on that.

raymo
04-01-2019, 07:42 PM
At least it is easy to collimate.
raymo

xelasnave
04-01-2019, 08:16 PM
Paul
Its always one thing after another...if my gear is ever totally functional I am sure the photos will be great but my fix it list is getting beyond me.
I would have thought your scope would be perfect for galaxies...I had thought of getting one for that but I really have not looked into it much...I ztill have two scopes to fix☺
Alex

The_bluester
04-01-2019, 08:17 PM
Certainly compared to something like an RC it is. I just did not get a chance to spend time on it with the mount issues.